Softball Excellence Foam Trainers (6 Balls per Pack) Lighter than a Nerf Ball, the Foam Trainer is designed to help pitchers and throwers increase the strength of their throws and learn to improve their control. Specifically designed with an extremely low mass, the Foam Trainer creates little resistance to air flow. This requires the pitcher to learn how to thrown very forcefully to generate distance. The Foam Trainer also responds to any slight change in hand direction at release- helping pitchers and throwers improve their control by showing them exactly where their hand was facing at release.